Scientists get never-before-seen look at supermassive black hole in our galaxy – and find unknown star nearby

(AFP via Getty Images)

Scientists have taken an unprecedented look at the supermassive black hole in our galaxy – and found an unknown star near to it.

The new research has allowed scientists to take an estimate of the black hole’s mass that is more accurate than ever before.

(ESO/GRAVITY collaboration)

Two studies covering the research are published today in Astronomy & Astrophysics is published today. Both include the work of Reinhard Genzel, who was awarded the Nobel Prize in 2020 for his work on the black hole, known as Sagittarius A*.

“We want to learn more about the black hole at the centre of the Milky Way, Sagittarius A*: How massive is it exactly? Does it rotate? Do stars around it behave exactly as we expect from Einstein’s general theory of relativity?” Genzel said in a statement.

“The best way to answer these questions is to follow stars on orbits close to the supermassive black hole. And here we demonstrate that we can do that to a higher precision than ever before.”

The new images are the deepest and sharpest ever produced of the supermassive black hole. Using the European Southern Observatory’s Very Large Telescope Interferometer, they zoom in 20 times more than what was possible before that equipment was switched on.

That extra detail allowed not only for the identification of the previously unknown star, but also to see the movement of other stars in more detail than ever before. That in turn can be better used to understand the black hole itself.

“Following stars on close orbits around Sagittarius A* allows us to precisely probe the gravitational field around the closest massive black hole to Earth, to test General Relativity, and to determine the properties of the black hole,” said Genzel.

The observations confirm that the stars are moving exactly as they are predicted by General Relativity, if the black hole is 4.30 million times that of our Sun. That gives us a closer estimate of the black holes mass than ever before.

They could also improve the estimate of its distance. The black hole is 27,000 light years away, the new research suggests.

The images were produced using a machine learning technique called Information Field Theory. That involved making a model of how the stars were expected to look, as well how they would appear through the instrument, and compare the two to produce more detailed images.